This apartment building with which Perret established his reputation is to be regarded as one of the canonical works of 20th-century architecture, not only for its explicit and brilliant use of the reinforced concrete frame (the Hennebique system) but also for the way in which its internal organization was to anticipate Le Corbusier's later development of the free plan. Perret deliberately made the apartment partition walls nonstructural throughout and their partial removal would have yielded an open space, punctuated only by a series of free-standing columns. As it is, each floor is organized with the main and service stairs to the rear (each with its own elevator) the kitchen to one side and the principal rooms to the front. These last are divided up from left to right into rooms assigned to smoking, dining, living, sleeping and reception...' p 116.